Land and water resources are significant constraints in the present energy scenario. Phyco-remediation is crucial in attaining the UNDP’s sixth sustainable development goal. The wastewater treatment by microalgae is highly economical, and the biomass generated can be further utilized for biofuel production. The successful coupling of microalgae with wastewater can overcome the expensive cultivation of microalgae and pollutants with wastewater and scale-up production of high-value products. A microalgae-based wastewater treatment process reduces BOD, inhibits coliforms, removes nutrients and contaminants, and removes heavy metals. In wastewater, nutrients are abundant, making it an ideal medium for growing microalgae. Microalgal biomass can produce a wide range of high-value products, such as biomethane, compost, biofuels, and animal feed.